1. Field of the Invention
The present invention relates to an improvement for a spray mechanism of an aerosol product for injecting the spray liquid from the container by a gas pressure by means of a vaporizing gas for spraying.
2. Description of Related Art
As the spraying mechanism an aerosol product using vaporizing gas a spraying gas, and injecting the spray liquid from the container by the gas pressure of this spraying gas, for example, the construction as shown in FIG. 7 has been previously known.
The device of FIG. 7 includes a container and a control member b, wherein the control member b is provided with a nozzle fitting hole c for fitting with the front end of a nozzle a1 of the container a, an injection hole d, and a leading path e for communicating with the nozzle fitting hole c and injection hole d, and by pressing down the control member b engaged with the front end of the nozzle a1 of the container a, the spray liquid in the container a moves from the nozzle a1 to the leading path e, and is injected from the spray hole d.
In FIG. 7, when the spray liquid decreases in the container a as a result of consumption, the gas space increases accordingly, and the internal pressure in the container decreases. As a result, when the container a is initially filled with the spray liquid and gas, the spray liquid is abundantly injected forcibly from the spray hole d, but when the remainder of the spray liquid becomes less than half, the injection of the spray liquid is no longer forcible, and a sufficient amount of spray liquid cannot be injected, and the state of atomization is poor at the same time.
Although not shown, as another spray mechanism for an aerosol product, aside from the type shown above, the so-called tilt type has been widely used, in which the liquid is injected from the spray hole by tilting the nozzle of the container.
In this tilt type, same as in the above type, the spray liquid forced out from the nozzle a1 by gas is injected from the spray hole by way of the leading path. Therefore, in this tilt type, too, as compared with the initial state, the injection force and atomization state of the spray liquid are poor near depletion of the container, and the same problems as above are present.
On the other hand, the conventional spray mechanism for an aerosol product was developed on the basis of using liquified gas represented by chlorofluorocarbons as the spraying gas. Such liquifies gas is gradually vaporized in the container a by proper amounts, so that the pressure in the container is kept almost constant from the beginning to the end of use, and the problems of deterioration of injection force and worsening of the atomization state were not apparently obvious.
However, disuse of chlorofluorocarbons has been decided from the viewpoint of environmental protection, and use of other liquefied gas such as LPG is difficult from the standpoint of safety. Hence, today, it is attempted to use CO.sub.2, N.sub.2, O.sub.2 and other vaporized gases as the spraying gas.
These vaporized gases (especially N.sub.2) are not dissolved well in spray liquid, and are mostly contained in the container a in a vaporized state. Accordingly, when used in the conventional spraying mechanism of an aerosol product, initially, the spray liquid is released at a high pressure, during contained use, the gas space increases, and the gas pressure in the container drops, and the container pressure is extremely low near the end of the content. As a result, the problems of deterioration of injection force and worsening of atomization state become manifest.
Still more, when liquified gas is used, a part of the liquified gas is injected together with the spray liquid. Hence, a part of the liquified gas is vaporized at the moment it is expelled from the nozzle a1, and acts to transform the spray gas into a fine mist, but in the case of vaporized gas, since it is not dissolved smoothly in the spray liquid, injection in such a fine mist state is not expected.
The invention is devised in light of these problems, and it is hence a primary object thereof to present a spray mechanism for an aerosol product capable of always maintaining a specific spray state and mist state from beginning until the end of use even when using vaporized gas.
It is another object of the invention to present a spray mechanism for an aerosol product capable of injecting a favorable fine mist even by using vasporized gas.